Valve control system



May 30, 1933. G. BLOCK VALVE CONTROL SYSTEM Filed Dec. 17, 1931 nveniio Gustav Bock,

His Atto'rneg.

Patented May 30, 1933 UNITED STATES PAT-ENT;

OFFICE GUSTAV BLOCK, OF OBERSCHONEVEDE, GER-MANY, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION 0F NEW YORK VALVE CONTROL SYSTEM Application filed December 17, 1931, Serial No. 581,560, and in Germany January 2, 1931.

My invention relates to valve control systems, more particularly to the rapid and positive control of valves in conduits containing gas under pressure.

A principal object of my invention is the provision of an improved valve control system whichV shall effect rapid opening and closing of the valves.

My invention Will be more fully set forth in the following description referring to the accompanying drawing, and the features of novelty which characterize my invention Will be pointed out With particularity in the claims annexed to and forming a part of this specication.

Referring to the drawing, the single figure thereof illustrates an elevational view, partly in section, of a valve control system embodying niy invention.

A valve control system on Which the present invention is an improvement is described and claimed in a co ending application Serial No. 451,388, filed ay 10, 1930, by Werner eberinuth for valve systems. This arrangement includes a main valve designed as a stepped piston, and a control valve, Which is substantially a duplicate of the main valve 0n a reduced scale, for relieving the pressure on one side of the main valve, thereby con-y trolling operation of the latter. In a stepped piston valve of the type above described the valve is seated by a force which isy proportional to the differential area of its two faces, when equal pressure Vacts on both faces. When the pressure acting on the larger face is relieved or reduced, as by connecting it to atmosphere, the piston is unseated by the excess pressure acting on its smaller face. The control valve which may be operated directly or indirectly by any suitable mechanism, controls an opening of su-ch size as to permit rapid venting of the space adjacent the larger face of the main valve. As the control valve is appreciably smaller than the main valve, it is operated rapidly by a comparatively small force and a correspondingly rapid reduction of the pressure acting on the larger face of the main valve results.

Referring more particularly to the drawing for an understanding of this arrangement, a suitable reservoir 1 containing gas under pressure for effecting a blast of gas, as in the operation of'gas blast circuit interrupters, has mounted thereon a valve casing 2 for the main valve, the casing communicating With the reservoir 1 through a pipe or conduit 3. VExtending from the casing 2 to the place of application of the gas flow are af conduit 4 and -a pipe 5 suitably connected thereto.

The casing of the control valve isy indi-n cated at 6 in Which is mounted a lever 7 suitably connected to actuating means, as a relay (not shown), for operating the controlV ranged to slide Within a corresponding cyl-- inder of the casing 2, and a smaller piston 11 Which controls a seat intermediate the pipes 3 and 4. A spring 12 engages the large piston 10 biasingit in a direction to seat the valve. For the purpose of equalizingpressure on opposite sides of theV main valve When it is normally closed, a small bore or passage 13 Within the piston connects the pipe 3 With a venting chamber comprising the cylinder in Which the piston 10 is mounted.

Interconnecting the main valve cylinder and the valve casing 6 is a pipe 14 including an opening 16 forming a seat for the control valve 15. The control valve 15, Which is similar to the main valve 9, is provided Witha large piston 17 corresponding tothe piston 10 of the valve 9 normally .biased by a spring 18 towards seating position.

When the control valve 15 islifted from its seat, assuming for the moment that opening 16 exhausts to atmosphere, the pressure Within the venting chamber of the piston 10 is rapidly relieved resulting in movement of the smaller piston 11 from its seat by the pressure existing in the conduit 3. Opening of the main valve results in a blast'of gas from the reservoir through the pipes- 4 and 5.

When the control valve l15 is seated pressure builds up in the venting chamber Within the casing 2 by reason of the gas admitted through the bore 13, so that the piston 10 is subsequently biased by the spring 12 to seating engagement terminating the gas blast.

For the purpose of operating the valve 15 the operating lever 7 is connected to a cam shaft 19 journaled within the casing 6 and provided with a cam 20. The shaft 19 is likewise connected to a piston 21 biased as by a spring 22 so as to control the position of the cam 2() withrespect to a valve stem 23 of an auxiliary valve 24. The valve 24 `is normally biased as by a spring 26 towards its seat, and controls, together with the atmospheric port 25, the pressure within the venting chamber or the control valve piston 17. lVith the cam 2O in the position shown, rotation of the cam shaft causes opening of the valve 24 so that the pressure Within the venting chamber above the piston 17 is reduced to atmospheric, and the valve 15 is immediately opened by the pressure existing within the pipe 14.

1t is undesirable that the main valve 9, interconnecting the conduits 3 and 4, remain open longer than is required. leclosing of the main valve within a short` time is effected by means of a pipe 27 interconnecting the pipe 5 and the venting chamber of the piston 21 arranged so that when gas pressure exists in the pipe 5 the piston 21 and cam shaft 19 are moved to the right causing disengagement of the cam 20. Spring 26 is now free to close the auxiliary valve 24 whereupon the control valve 15 is seated. A bore 15 serves to equalize pressure on opposite sides of the valve 15 in the manner previously described.

For the purpose of preventing operation of the main valve when the pressure in the gas reservoir is below a predetermined value a valve 28 suitably mounted within a valve casing 29 is operatively connected by means of a pipe 30 with the reservoir 1. The reservoir pressure acts on the' valve 28 against the bias of spring 31 and when the gas pressure is too low the valve is opened by its spring admitting gas under pressure by way of therpipe 32 to the piston 21. As in the previous case the piston 21 is biased against its spring so that the cam 2() is inoperative with respect to valve 24 thereby preventing actuation of the main valve. When the. pressure in the reservoir has attained its normal value the valve 28 closes and the gas under pressure within the pipe 32 is relieved by way of a bore 33 in the cylinder of piston 21.

In contrast to the opening speed of the main valve, it is closed however at comparatively slow speed by reason of the fact that the` air escape or venting chambers in the main and control valves must be reilled in succession and through small apertures. The main valve therefore remains open for a longer time than is absolutely necessary and the gas blast continues after circuit interruption. I

For the purpose of reclosing the main valve rapidly the venting chambers of the valves are collectively or individually filled with compressed gas after operation of the main valve. The compressed gas may be taken at a point beyond the main valve from the pipe through which the blast is directed. With this arrangement the blast is continued for a short time at full pressure, after which the main valve is rapidly closed. Since the venting chambers are under pressure whenV the valves are closed, the connecting pipes provided for reilling said chambers are provided With means, as non-return valves, afording passage of the compressed gas from the pressure line. Likewise in order to vary the time limits in which the main valve is closed, throttling valves, as butterfly valves, maybe provided in the pipes leading to the venting chambers so that the refilling operation progresses more or less rapidly.

To this end the pipe 27 is connected with the venting chamber above the piston 17 by means of a pipe 34 in which is positioned a one-way valve 35, as of the seated ball type. In a similar manner the venting chamber behind the piston 10 is in communication with the conduit 4 by means of a pipe 36 in which a valve 37 is located. When the main valve is opened in the manner above described the gas blast within the conduits 4 and 5 transmits pressure by way of the pipes 27-34 and 36 to the venting chambers of the valves 15 and 9 respectively. With flow of gas in this direction the valve 35 freely admits compressed gas to the chamber above the piston 17, whereas the throttling valve 37 is arranged to throttle the gas to a certain eX- tent.

that the main valve Will close sooner since its closing obviously depends upon prior closing' of the valve 15. Likewise the closing of valve 15 is accelerated by the full gas pressure acting thereon. kAfter closing of this valve the one-way valve 35 prevents escape of compressed gas which is admitted through bore 15 after the main valve is closed.

For the purpose of further shortening the time of closingV of the main valve pressure may be applied directly from the conduit 4 to the venting space behind the main valve as by the pipe 36, .the flow of gas being controlled by the .throttling valve 37. In order that thethrottling valve shall not retard the relief of pressure from the pipe 14k when the valve 15 is opened, the valve is preferably arranged as shown so that its throttl'mg action occurs only during flow of gas from the source of pressure to the venting chamber of the main valve. Or, in lieu vof this arrangement, a non-return valve may be disposed in parallel relation with the throttling valve. By suitable adjustment of the throttling valve it will be apparent that gradation of the closing speed of the main valve may be within narrow time limits. This will be apparent since the pressure within the venting chamber of valve 9 has built up substantially by the time the control valve l5 has closed, thereby shortening the closing period.

It should be understood that my invention is not limited to specific details of construction and arrangement thereof herein illustrated, and that changes and modifications may occur to one skilled in the art without departing from the spirit of my invention.

Vhat I claim as new and desire to secure by Letters Patent of the United States is:

l. A valve controlVK system comprising a source of gas pressure, a main valve controlling release of gas from said source, a control valve for relieving pressure on one side of said main valve so that said main valve is immediately opened b y pressure acting on another side thereof, means including a venting chamber for relieving pressure on one side of said control valve causing opening thereof, and means effecting rapid closing of said control valve including an unrestricted pressure communicating connection between said venting chamber and a point in the system beyond said main valve.

2. A valve control system comprising a reservoir containing gas under pressure, a main valve controlling a blast of gas from said reservoir, means including a venting chamber in which the pressure acting on said main valve is equalized during the closed position, a control valve for relieving pressure in said chamber causing immediate opening of said main valve, said control valve also having a pressure equalizing chamber venting of which causes opening of said control valve, and means eifecting rapid closing of said control valve including a pressure communicating connection between said pressure equalizing chamber and a point in the system beyond said main valve, said connection having a one-way valve preventing relief of pressure in said chamber by way of said connection.

3. A valve control system comprising a source of pressure, a main valve controlling release of said pressure, means including a. pressure equalizing chamber controlling operation of said main valve, means relieving the pressure in said chamber causing immediate opening of said main valve, and means accelerating reclosing of said main valve including a direct pressure communicating connection between said venting chamber and a point in said system beyond said main valve for rapidly refilling said chamber with gas under pressure.

4. A valve control system comprising a reservoir containing gas under pressure, a conduit forming a gas exhaust from said reservoir, a main valve in said conduit controlling said eXhaust, said main valve having a venting chamber normally retaining gas under pressure equalizing pressure on said main valve, a control valve for relieving the pressure in said chamber causing immediate opening of said main valve, said control valve likewise having a pressure equalizing chamber, means relieving the pressure in said last-named chamber causing actuation of said control valve, and means rapidly refilling the chamber of the control valve with gas under pressure causing immediate reclosing thereof including a direct connection between said chamber and a point in said conduit beyond said main valve.

5. A valve control system comprising a reservoir containing gas undervpressure, a conduit forming a gas exhaust from said reservoir, a main valve in said conduit controlling said exhaust, means including a pressure equalizing chamber associated with said main valve, a control valve for venting said chamber causing immediate openingof said main valve, means including a second pressure equalizing chamber associated with said control valve, means venting said last-named chamber causing opening of said control valve and consequent venting of said Vfirstnamed chamber, and means accelerating the closing of said control valve comprising a pressure communicating connection between the pressure equalizing chamber of the control valve and a point in said conduit beyond said main valve, said connection including a one-way valve permitting refilling of said chamber with gas under pressure immediately after venting thereof, and a second pressure communicating connection between the chamber of said main valve and a similar point in said conduit arranged so that said last-named chamber starts refilling with gas under pressure after opening of said main valve, said second connection being opened by said control valve for venting said chamber.

In witness whereof, I have hereunto set my hand.

GUSTAV BLOCK. 

